Yams for Sale in Market (IMAGE) Earlham Institute Caption Woman selling yam tubers at Oje market, Ibadan. Credit Creative Commons by International Institute of Tropical Agriculture Licensed with CC BY NC 2.0 Usage Restrictions May only be used as per CC BY NC 2.0 license, with full attribution to the International Institute of Tropical Agriculture. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.